View Full Version : Ghost or motion blur "effect" problem


Jarda Bar
January 11th, 2010, 01:59 PM
I have found problem with my A1 camcorder. When I take a shot of fast moving object, picture contains ghost. You can seen this artifacts in this picture:

full resolution screenshot: http://www.jardabar.net/temp/CanonXH_A1_blur.jpg

Have some one any idea to resolve this problem, please?
p.s.: Noise reduction is off.

Michael Hutson
January 11th, 2010, 03:50 PM
Need a bit more info on your camera settings. I am guessing low shutter speed. What mode were you using?

Jonathan Shaw
January 12th, 2010, 01:20 AM
I reckon somewhere along the way frame rate or shutter speed are you problem, as pre previous post need more info.

Jarda Bar
January 12th, 2010, 03:32 AM
It has been taken with: 1/100, 25F ... custom preset with NR1 and NR2 off.

Olivier Depaep
January 12th, 2010, 03:48 AM
Did you zoom in a lot?

Jarda Bar
January 19th, 2010, 02:26 PM
May be it was 50% of max. zoom.

Matthew Amirkhani
January 19th, 2010, 07:28 PM
Hi Jarda,

Will you tell me which NLE program you're using? and what is the setting of it?

Jarda Bar
January 21st, 2010, 03:25 AM
Hi Matthew!
It's Vegas 9.0c, HDV 1080@25p, progressive scan ... this picture has been taken from original captured video clip m2t.

Bo Sundvall
January 21st, 2010, 04:26 PM
Hi

Image Stabilizer on or off?


Regards,

/Bo

Jarda Bar
January 25th, 2010, 01:20 AM
OIS was On.

Bo Sundvall
January 25th, 2010, 09:19 AM
Hi

Try to set it to off. Image stabilization is good in some situations but might give unwanted effects in other situations. Using a camcorder on a tripod is a situation when it's not so good. I believe that fast motion following a moving object also might generate unwanted effects as the image stabilizer is trying to, ehh, stabilize the image....


Regards,

/Bo

Howard Churgin
January 25th, 2010, 12:26 PM
I regularly video horseback riding and equestrian jumping which requires handheld work and all panning. I shoot 60i with OIS on and never have any issues. The only time i did have an issue is when i tried 30p and 24p shooting. Then the motion artifacts were terrible. But at 60i i even pull terrific slo-mo in PPro and After effects.

Peter Manojlovic
January 25th, 2010, 10:00 PM
Take it to the local Canon repair depot...
I had a similair issue. Although it was during low lighting, the effect was similair..

The problem had something to do with the autofocus sensor.

The $100-$200 to get them to check the unit might give you some piece of mind.

Chris Soucy
January 25th, 2010, 11:08 PM
I've looked at those pictures now maybe a dozen times and haven't chimed in because I simply could offer no rational explanation that fitted the shooting parameters you have quoted.

Well, I've just looked again and a glimmer of an idea occured to me.

The subject (toboganer) is as clear as a bell, no ghost/ after/ pre image which means he/ she/ it was held pretty well constant in the frame for the previous 4 or 5 fields/ frames.

Everything else, most easilly seen with the forground trees, has at least 4 pre images ghosting the frame.

Now, tell me, what was the air temp when that shot was taken and has this happened at any other time when the air temp was "normal" ie: above say, 5 degrees C?

What I'm thinking is this:

The ghosts are images of the objects as they were in preceeding fields/ frames (you can see how the oldest, right hand most, has faded the most, the immediate previous, hardly at all), they simply have not been entirely erased, and made all the more visible by being outlined against a pure white background.

Now, this could be something that happens on all cameras, all the time under similar shooting conditions and it's just never seen due to the lack of a pure white background, though I have my doubts about that, otherwise the Winter Olympics would be pretty naff on telly,

OR

There is a fault with the camera electronics not clearing the CCD between fields/ frames and thus fixable.

OR

It's neither of the above and it is, indeed, the OIS stepping to try to eliminate the unwanted movement of the camera.

My problems with that latter supposition are these:

It would have had to have stepped (and stopped, briefly) at least 4 times and possibly more in the space of 1/100th of a second. Guess it's possible but sure seems fast to me.

Then, how come the toboganer is as sharp as a tack? If the OIS is stepping around like Fred Astaire, the toboganer should be ditto and also have pre/ post image ghosts. Does not compute.

'Fraid that's my best shot with the data to hand.


CS

Jarda Bar
January 26th, 2010, 02:39 PM
First of all, many thanks to all of you.

Because, I haven't enough time to make any investigation in past few days, I didn't step forward. But yesterday, I'll go to test my camcorder to the same place and because temperatures are still bellow zero (-7°C), it will be same situation.
I will try to record video in 25F and 50i mode etc. and put results to this thread.

It doesn't seems like OIS issue for me, maybe Chris is right and there is problem in low temperatures with A1 . I never found ghost effect in my footage before.

Jarda Bar
January 27th, 2010, 04:08 PM
Today, I tried to reproduce ghosts problem, but without success. It seems like short indisposition of A1 ... tomorrow I will make last test.